A PPE resin is a thermoplastic resin having excellent various properties such as mechanical properties, a heat resistance, a dimensional stability, etc. However, the PPE resin is very poor in impact characteristics and solvent resistance by itself, and also is poor in processability due to a high melt viscosity thereof.
On the other hand, a PA resin is a thermoplastic resin having characteristics of excellent mechanical properties, solvent resistance, processability, etc., but the resin is poor in impact resistance, heat resistance, etc., and is also greatly poor in dimensional stability due to a large water absorption property thereof. Further, the PA resin shows severe decrease in mechanical characteristics due to water absorption.
Thus, it has been proposed to blend both the resins to supplement the faults of these resins each other.
However, a simple blend of these resins loses good mechanical characteristics of these resins. Thus, it has been proposed to attain the improvement on the mechanical properties of the resin blend by adding a compatibilizing agent to the mixture at blending the PPE resin and the PA resin to improve dispersibility. These methods are disclosed in JP-B-60-11966, JP-B-61-10494 (the term "JP-B" as used herein means an "examined published Japanese patent application"), JP-A-59-66452, JP-A-56-49753, (the term "JP-A" as used herein means an "unexamined published Japanese patent application"), etc. The PPE/PA series resin composition thus obtained has been used in electric and electronic fields and automobile field as a material having excellent mechanical properties, heat resistance, solvent resistance, processability, dimensional stability, and hygroscopic properties.
Recently, a natural environmental disruption by industrial activities has been noticed and resource saving has become an important problem. In the field of resins, the re-utilization of resins by recycling has been positively proceeded.
However, in the above-described PPE/PA resin composition, etc., if recycling of the resin composition by, for example, injection molding is conducted, a phenomenon occurs that the flowability is greatly increased due to deterioration of the resin composition. Also, in a system of compounding a talc, etc., with the resin composition, a phenomenon occurs that the flowability is conversely decreased. Accordingly, when a mixture of a virgin resin and a recycled resin is molded, the melt flowability of the mixed resin composition is greatly changed with the mixing ratio.
Thus, if the molding conditions are not controlled with every change of the mixing ratio of the resins, moldings showing a large shrinkage or defective molding products having burrs at the circumferences are formed, resulting in a serious problem for the quality control.
Therefore, a resin showing small change in the melt flowability at recycling has been required.